Fuzing systems function as part of military ordnance in part by providing independently determined redundant confirmations of specific conditions that must be met prior to the removal of the safety locks which would otherwise prevent warhead function. Design criteria governing the operation of arming devices as part of fuzing systems is established by MIL-STD-1316, which requires that the design of the fuzing system include the ability to discern and evaluate at least two independent physical conditions confirming a proper launch of the warhead. These conditions are selected according to the anticipated operating profile of the warhead, and implemented in such a way that they cannot be simulated or artificially induced by accident, such as by mishandling of the warhead by weapons handling personnel. For example, an artillery projectile may experience launch acceleration of 15,000 earth gravities (483,000 ft/sec/sec) and spin rates, induced by the rifling twist in the barrel, of 90,000 rpm when fired, neither condition being easy to create in any condition other than an actual gun firing. In certain implementations, the two independent physical conditions such as launch acceleration and spin may be discernible simultaneously or sequentially within specified periods of time. In these ways a physical “signature” that cannot be artificially induced is defined, and the arming device will arm, thereby permitting subsequent detonation of the explosive warhead.
As ordnance systems have evolved, and specifically as ballistic trajectory projectiles have evolved into guided projectiles, spin, a frequently used and universally accepted physical condition, is no longer available. In particular, guided projectiles, missiles and rockets achieve improved accuracy at conventional or extended range by using aerodynamic control surfaces to fly to a designated target. Aerodynamic control surfaces, however, would be destroyed by the spin rates of ballistic flight; therefore spin must be suppressed or eliminated. With spin eliminated, one of the most commonly used signatures for proper launch is not available for use in the fuzing systems of guided weapons.
Accordingly, a need exists for a warhead fuzing system utilizing an alternative condition for confirming the proper launch of the warhead before the warhead is armed.